I have been a practicing dental hygienist for 30 years in the state of Virginia.  The  primary duty of the dental hygienist in any general or specialized practice is to disinfect  the oral cavity.  The disinfection of course includes scaling and removal of all biofilm  to promote good oral and systemic health.  The llink between systemic and oral health has allowed our dental profession to join the interdisiplinary health team. Only  registered and licensed Dentists and Dental Hygienists in the state of virginia are truly educated and responsibe for this privledge.  The expansion of duties to allow dental assistants to  "scale" would be nothing but a step backwards in our path to total health.